Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Stroke impairs learning also in remote brain regions; first success with new therapeutic approach

25.08.2011
Stroke patients often have difficulties with re-learning simple skills such as walking or talking, and the causes are still unknown.

In a new study, researchers from the Bernstein Network and the Universities of Göttingen and Jena now show that a stroke even affects the learning ability of remote brain areas. Learning processes in the visual system of mice were impaired, in some cases even for weeks. The scientists conclude that plastic brain changes are modulated by networks far bigger than previously assumed. By administration of anti-inflammatory drugs, some of the networks were able to regain their learning ability.

In Germany alone, every year some 200,000 people suffer from strokes. It is still not understood why the affected subjects often find it so difficult to relearn everyday abilities. There are still debates about the best starting time for therapy and the best approach towards medication. Scientists have long observed that the localized blood flow disturbance can also affect distant brain areas. Now scientists led by Professor Siegrid Löwel and Professor Otto Witte have examined the effects of a local stroke on neuronal plasticity in the visual system of mice as part of the “Visual Learning” project of the Bernstein Focus: Neuronal Basis of Learning.

Closing one eye in healthy animals leads to an increase in the visual acuity of the remaining eye, and both hemispheres process information from the open eye more intensely. “We have shown that the brain loses this ability after a stroke,” says Franziska Greifzu, PhD student in the laboratory of Prof. Siegrid Löwel, a neurobiologist at the Bernstein Focus Neurotechnology and the University of Göttingen, and head of the study. For the investigation, a stroke was induced in an area of the cerebral cortex that has no known effect on the visual system. Closing one eye immediately after the stroke resulted in the mouse brain being unable to normally adapt to the new situation; it had lost its ability to learn. Two weeks after the brain damage, the ability to adapt was partly regenerated.

The researchers examined whether inflammation could be responsible for this compromised learning. Therefore, they treated the animals immediately after the stroke with an anti-inflammatory drug. The result was that the treated animals developed, as with healthy animals, an increased visual acuity of the open eye. “The impaired learning ability after a stroke could be rescued to normal levels by use of anti-inflammatory drugs”, explains Witte, a neurologist at the University Hospital of Jena.

How the damaged area of the brain affects the visual system is still unclear. “There are obviously a lot more interactions between brain areas than we know and usually test experimentally,” says Löwel. Now the scientists want to examine more closely what changes a stroke entails on the cellular level and how learning ability can be completely restored. The results were published in the renowned scientific journal PNAS.

The project “Visual Learning” of the Bernstein Focus: Neuronal Basis of Learning is part of the Bernstein Network Computational Neuroscience (NNCN) in Germany. The NNCN was established by the German Federal Ministry of Education and Research with the aim of structurally interconnecting and developing German capacities in the new scientific discipline of computational neuroscience. The network is named after the German physiologist Julius Bernstein (1835–1917).

Original publication:
Greifzu et al. (2011): Global impairment and therapeutic restoration of visual plasticity mechanisms after a localized cortical stroke. PNAS, published ahead of print August 24, 2011, doi:10.1073/pnas.1016458108.
For further information please contact:
Prof. Dr. Siegrid Löwel
sloewel@gwdg.de
Systems Neuroscience Group
Bernstein Focus: Neurotechnology (BFNT) and
J.F. Blumenbach Institute of Zoology and Anthropology
Göttingen University
Von-Siebold-Str. 4
37073 Göttingen
Germany
Phone +49 (0) 551 3920161/60

Johannes Faber | idw
Further information:
http://www.nncn.de/
http://www.uni-goettingen.de/
http://www.uni-jena.de/

More articles from Studies and Analyses:

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

Im Focus: Optoelectronic Inline Measurement – Accurate to the Nanometer

Germany counts high-precision manufacturing processes among its advantages as a location. It’s not just the aerospace and automotive industries that require almost waste-free, high-precision manufacturing to provide an efficient way of testing the shape and orientation tolerances of products. Since current inline measurement technology not yet provides the required accuracy, the Fraunhofer Institute for Laser Technology ILT is collaborating with four renowned industry partners in the INSPIRE project to develop inline sensors with a new accuracy class. Funded by the German Federal Ministry of Education and Research (BMBF), the project is scheduled to run until the end of 2019.

New Manufacturing Technologies for New Products

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

A new technique isolates neuronal activity during memory consolidation

22.06.2017 | Life Sciences

Plant inspiration could lead to flexible electronics

22.06.2017 | Materials Sciences

A rhodium-based catalyst for making organosilicon using less precious metal

22.06.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>